<div id="maplegend">
  <div id="legend_body" *ngIf="legendDown">
    <img *ngFor="let item of data" src="{{item}}">
  </div>
  <div id="legend_bottom">
    <i class="icon ion-logo-buffer" id="legend_icon"></i>
    <span>图例</span>
    <i nz-icon id="legend_ud" [nzType]="legendDown? 'up':'down'" nzTheme="outline" (click)="arrowClick()"></i>
  </div>
</div>